Apparatus for grinding the surfaces of grooved rolls



July 6, 1948- H. A. THORNGREN 2,444,793l

APPARATUS FOR GRINDING' THE SURFACES 0F GROOVED ROLLS Filed April 2e, 1945 2 sheets-sheet 1 H. A. THORNGREN APPARATUS FOR GRINDING THE SURFACES OF GROOVED ROLLS 2 Sheets-Sheet 2 Filed April 26, 1945 INVENToR.

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Patented July 6, 1948 APPARATUS FOR GRINDING THE SURFACES F GROOVED ROLLS Helmer A. Thorngren, Detroit, Mich.

Application April 26, 1945, Serial No. 590,338

Claims.

The invention relates to a rotary grinding mechanism and it has particular relation to a mechanism for grinding the surfaces of grooved rolls.

In the manufacture of tubing or a similar product, the tubing is passed between pairs of rolls having grooves which jointly form an opening through which the tubing travels. Necessarily, if precision is to be obtained, the rolls must be accurately formed or shaped, and the rolls of each pair must have mating contours. In actual practice heretofore, in so far as known, these rolls have been individually vshaped and ground, and therefore, precision depends upon individual atn tention given to each roll. It follows that if either of a pair of rolls varied from the other, their surfaces would not be truly mating in character. Furthermore, a great amount of time and work is involved in grinding the rolls individually and the operation is extremely costly especially if any degree of precision is to be obtained. I

Oneobject of the |present invention is to provide an apparatus for grinding a pair of mating rolls which enables obtaining the precision and mating characteristics required in a simple, inexpensive, and efficient manner.

Another object of the invention is to provide an improved apparatus for grinding a pair of rolls simultaneously to the end that the surfaces on both rolls will be ground in the same operation by a single grinding wheel.

Another object of the invention is to provide an apparatus such as indicated which enables quickly placing the wheels in position for resurfacing or grinding and then quickly removing them after the grinding operation.

Another object of the invention is to provide an apparatus such as indicated which is adjustable so the rolls may be properly centered and also so that rolls of diierent sizes and curvature may be readily resurfaced or ground. l

Another object of the invention is to provide an apparatus for the purpose indicated which may be readily attached to an ordinary lathe so that it may be made available at a reduced cost and also so that it may be more widely used without requiring special machine setups.

Other objects of the invention will become apparent from the following specication, from the drawings relating thereto, and from the claims hereinafter set forth.

For a better understanding ofthe invention, reference may be had to the drawings wherein:

Figure 1 is a front or end View of apparatusor mechanism constructed 'accordingto one form of Ams 2 the invention as seen along the line I -I of Fig. 2;

Fig. 2 is a side elevational View of the mechanism;

Fig. 3 is a cross-sectional view taken substantially along the line 3-3 of Fig, 1;

Fig. 4 is a cross-sectonal view taken substantially along the line 4-4 of Fig. 1;

Fig. 5 is a cross-sectional view taken substan tially along the line 5--5 of Fig. 4; and,

Fig. 6 is a cross-sectional view taken substantially along the line 6-6 of Fig. 1.

Referring to Figs. 1 and 3, the mechanism is shown in conjunction with a lathe, and for 'the purpose of simplicity only the face plate andbed of the lathe are shown as indicated respectively at` -Ill and I I. The apparatus principally =is mounted on a circular plate I2 which is fastened to the face plate by means of upper bolts I3 and lowerbolts I4. These bolts have rectangular heads I5 `at one end which fit in radial slots I6 of the character usually provided on the face plate of a lathe. The upper bolts I3 have nuts I I on their outer ends which clamp the two plates together, but the lower bolts are shorter and the nuts on these bolts indicated at I9 are located in circular openings 2l) inthe plate I2 so that neither the ends of the bolts nor the nuts thereonat the lower side of the plate project above the outer surface of the plate. These plates are assembled so that they are concentric and it will be noted that they have substantially the same radius so thattheir outer peripheries are ush.

It has been mentioned previously that the apparatus is provided for the purpose of `grinding Ia pair of rolls, and these rolls are indicated at 22 and 23, respectively. The roll 22, as best shown by Figs. 4 and 5, has a grooved periphery indi'- cated'at 2B and an inner hub 2l provided with a keyway 2'8. The hub is adapted to be drivingly connected to a sleeve 29 having la key 3l) fitting the-keyway 28, and the hub 21 in turn is drivingly connected to a shaft 3| by means of a `key 32. For locating the roll aXially,`a shoulder 33 may be provided on the shaft, and the roll is pressed on until it reaches the shoulder. The roll 23 is of the same character and is mounted on a shaft 34 extending upwardly in parallel relation to the shaft 3 I. It will be noted in Fig. l that the rolls may be readily removed by upward pressure, and in this connection it should be understood that they are mounted with suflicient tightness on the shafts that they will stay in position during revolving thereof about the axis of the lathe.

The shaft 3| is journalled in openings in'legs 35 and 36 projecting outwardly from ablock 31,

and this block, as best shown by Fig. 6, has a dovetail 40 which is slidable in a dovetail slot 4l formed in a second block d2. Similarly, the shaft 34 is journalled in legs 43 and 44 projecting outwardly from a block 45 which also has a dovetail 46 slidable in the slot 4l. The slot and dovetails are directed perpendicularly to the axis of the shafts 3l and 34, and consequently the shafts and rolls may be adjusted towards and from each other ini a direction perpendicular to their axes.

For the purpose of adjusting the blocks 4U and 45 in the manner stated, a screw 48 is provided with threaded portions i3 and 5d which-are op posite in character, and these two threaded portions are respectively threaded through the blocks. Rotation of the screw 48, therefore, will cause the blocks to move towards eachother or away from each other, depending upon direction of rotation. The outer end of this screw indicated at 5l may be square or polygonal to facili- .tate adjustment or turning of the screw, and if desired, suitable means may beprovided' for holding the screw in any adjusted position.

, Theblock 42 hasa dovetail 53 which is slidable in a dovetail slot 54' in the plate I2'. This dove- -tai=l= and slot areA directed parallel to the shafts 3l and 34 so that therolls may be adjusted in the direction of their axes. Adjustment of the block 42 is effected' by means of a screw 55, shown Figs; 1 and 3, which is threaded through a boss 5B on the plate i2. This screw projects upwardly intothe block 42 and has a collar 5i on its upper .end located in a slot 58 in the block. From this itiiol-lowsth'at rotation of the screw will move the block 4,2- andv all parts carried thereby, vertically in one direction or the other depending upon direction` of movement desired.

The" sha-ft 3i: is provided with a` worm 60 meshing with al worm 8 I- on a drive` shaft 62 extending between the legs 35 and 3G,` and similarly, the f shaft 34? has a worm iidv meshing with a worm 65 erry the drive shaft. The drive shaft 6-2 is journalied at its ends in bearings indicated generally at 6T and t8-, and these' bearings may be fastened to the plate I2 by screws 69. It may' be mentioned" inf connection with such bearings that they may involve roller or plain .cylindrical bearings, andthat the shaft 52 will be held' against endwise movement during its rotation by any suitable thrust means. Likewise, the shafts 31: and 34 maybe journalled in the legs 35 and 36', and 43 and 44, respectively, byY suitable bea-rings which will holdithe shafts against axialmovement while permitting their rotation.

One end. of the shaft B2 has a pinion 1.0 drivingly connected thereto and this pinion meshes with? a second pinion ll mounted ona short stub-shaft 'l2 journalled'in` a bearing '13 fastened by` screws i4 to theyplate l2. The pinion 'H is in me'slrwith a ringl gear 15 which encircles theface platev I0- of the lathe and they plate I2V fastened thereto, and the teeth indicated at 'Hf are on the frontside of the ring. The ring is held in a` stationary position` by means of al bracket 'i8V having oppositely disposed arcuate leg portions 19 and- Bll-ffittingopposed portions of theV gear and which are: fastened solidly thereto by bolts 8l. This bracket is-held on the bed' I lofthe lathe by one or-more bolts 83;

Grinding of th'e grooved surfaces of therolls isl accomplished by a grinding wheel 85 which is mounted: on a shaft 86. This shaft and grinding wheel may be driven by: any suitable means suchas by an electric motor 6"! or otherA power drive, and-.it may beine-unted` on the lathe in any suitable manner. As shown by Fig. 2, the motor 81 is shown on a cross slide 88 having a dovetail 89 which' is slidable in a slot 90 formed on a saddle 9i. This saddle is slidable on the ways of the lathe bed and is adjustable therealong in the usual manner such as by an adjusting screw. The cross slide 88 is adjustable along the slot 90 and a screw 92 may be used for adjusting the slide. Hence; the motor may be moved longitudinally" and transversely of the lathe.

In operation, the lathe is rotated at a relatively slow speed and this causes rotation of the rolls and, allparts carried by plate l2. During this rotation, the pinion ll is driven through its engagement with the stationary ring gear 16 and rotation of the pinion 'Il in turn causes the two rolls to be driven slowly about their own axes in the directions shown by the arrows in Fig. l. It .follows that the rolls are driven about their own axes at the same time that they are revolving about the axis of the lathe. With the grinding wheel in position betweenr the rolls and in contact with the surface on either roll, rotation Aof the rolls about their own axes and simultaneousrevolving thereof about the axis of the lathe, will effect grinding of thecomplete surface of theroll as theoperationcontinues. It is evident that the curvature of both the roll: surfaces Will correspond exactly to each other since they are passing the same grinding wheel and are rotating about the same axis. As a result, both' rolls will have the same: surface contour. When the operation is completed, it is a simple matter to Withdraw the grinding wheel and remove the rolls from-thc shafts.

It is evident that rolls of: different sizesand different contours may be' ground by making adjustments such as have been described and shown. By moving the rolls farther apart, and shifting the grinding wheel farther away from the axis of the lathe, the surface` of the rolls may be ground with a larger radius and vice versa, by bringing the rolls close` together they may be ground with a smaller radius. As shown, the rolls are suiiciently close together that the two grooves practically form a complete circle for a tube whichl in practicel passes between the rolls;

The plate I'2 may be readily mounted onthe face plate of any lathe, and the ring gear 16 and its bracket 18' likewise may be easily mountedA and placed on the bed of the lathe. This completes the` mounting for supportingr the rolls and driving them, and it is only necessary to place the rolls in position and make the necessary adjust-` ments. The grinding wheelv is mounted separately and may be easily fastened to the cross slide or if desired, it could be fastened on the lathe in other ways. In any event mounting of the entire apparatus is a simple matter and operation thereof is likewise simple and notcomplicated.

Although only one form of the invention has been. illustrated and described in detail,.it.wil1 be .apparent to those skilledy in the art that various modifications may be made without departing from the'scope of the claims.

What is claimed is:

l; In an apparatus for grinding the surfaces of grooved rolls, a support for a pair of rolls tobe ground, means for rotating the support about a predetermined axis, means for mounting thel rolls on the support so that they will be disposed in planes radial to said axis, means for driving the rolls about their own axes respectively while they are being revolved about the axis of the support, and means for adjusting the rolls ra-dially of the 4axis of the support.

2. In an apparatus for grinding the surfaces of grooved rolls, a support for 'a pair of rolls to be ground, means for rotating the support about a predetermined axis, means for mounting the rolls on the support so that they will be disposed in planes radial to said axis, means for driving the rolls about their own axes respectively While they are being revolved about the axis of the support, means for adjusting the rolls radially of the axis of the support, and means for adjusting the rolls along their own axes.

3. An apparatus for grinding the surfaces of grooved rolls comprising a plate mounted for rot'atio-n about an axis perpendicular to the plate, a pair of shafts on the plate in positions perpendicular respectively to radii of said axis, means on each of said shafts for holding a roll, means for rotating the plate, means for rotating the shafts as 'the plate is rotated, and means for adjusting the shafts and rolls radially of the` plate axis.

4. An 'apparatus for grinding the surfaces of grooved rolls comprising a plate mounted for rotation about an axis perpendicular to the plate, a pair Aof shafts on the plate in positions perpendicular respectively to radii of said axis, means for Iadjustably supporting the shafts o-n the plate so that they are adjustable radially of said axis While being held equidistant from such axis, means for rotating the plate, means for rotating the shafts as the plate is rotating, and means on each shaft for holding one of the rolls.

5. An apparatus for grinding the surfaces of grooved rolls comprising a plate mounted for rotation about an axis passing through the plate, a pair of shafts on the plate in positions perpendicular respectively to radii of said axis, a third shaft extending transversely of the pair of shafts, drive connections between the third shaft and the pair of shafts so that the latter 'are driven when the third shaft is driven, a stationary ring gear concentric to the plate axis, a gear connection between the third shaft and ring gear, and means for holding a roll on each of said pair of shafts.

6. An apparatus for grinding the surfaces of grooved rolls comprising a plate mounted for rotation about 'an axis passing through the plate, a, pair of shafts on the plate in positions perpendicular respectively to radii of said axis, a third shaft extending transversely of the pair of shafts, drive connections between the third shaft and the pair of shafts so that the latter are driven when 'the third shaft is driven, a stationary ring gear concentric to the plate axis, a gear connection between the third shaft :and ring gear, means for holding a roll on each of said pair of shafts, and means for adjusting said pair of shafts towards or from each other.

7. In combination with a lathe, an apparatus for grinding the surfaces of grooved rolls comprising a supporting plate, means for mounting the plate on the face plate of the lathe, a pair of shafts on the supporting plate, a ring gear mounted on the bed of the lathe in concentric relation tc the axis of the lathe, a third shaft on the supporting plate, gear means drivingly connecting the ring gear to the third shaft, means drivingly connecting the third shaft to said pair of shafts, and means for holding a roll on each of the pair of shafts.

8. In combination with a lathe, an apparatus for grinding the surfaces of grooved rolls comprising a supporting plate, means for mounting the plate on the face plate of the. lathe, a pair of shafts on the supporting plate, a ring gear mounted on the bed of the lathe in concentric relation to the axis of the lathe, a third shaft on they supporting plate, gear means drivingly connecting the ring gear to the third shaft, means drivingly connecting the third shaft to said pair of shafts, means for holding a roll on each of the pair of shafts, means for adjusting the shafts tof wards or from the plate axis, 'and means for adjusting the shafts along their axes.

9. An apparatus for grinding the surfaces of grooved rolls comprising a supporting plate, means for mounting the plate on the face plate of fa. lathe so that it will turn about the lathe axis, a pair of shafts on the supporting plate disposed normal to radii of the plate axis of rotation, means for holding a roll on each shaft, a third shaft on the plate, gear means drivingly connecting the third shaft to the pair of shafts, and means for adjusting the pair of shafts towards or fro-m the plate axis.

10. An apparatus for grinding the surfaces of grooved rolls comprising a supporting plate, means for mounting the plate on the face plate of a lathe so that it will turn about the lathe axis, a pair of shafts on the supporting plate disposed normal to radii of the plate axis of rotation, means for holding a roll on each shaft, Ia third shaft on the plate, gear means drivingly connecting the third shaft to the pair of shafts, means for adjusting the pair of shafts towards or from the plate axis, and means for adjusting the pair of shafts along their own axes, respectively.

HELMER A. THORNGREN.

REFERENCES CITED UNITED STATES PATENTS Name Date Hipwell Aug. 1, 1876 Number 

